The present invention is related to an electronic talking stick for the blind to help a blind man to walk, which utilizes synthetic voice to inform passers or the blind man of the existing situation. It indeed helps to solve the problems a blind man may encounter while carrying a conventional stick or being guided by guide dog.
In U.S. Pat. No. 4,280,204, a cane for the blind provided with an ultrasonic obstacle sensing apparatus is disclosed, wherein a transducer 16 is mounted on shank portion 14 of the cane 10 to transmit and receive a directional, multiple lobe pattern of ultrasonic energy, whereby when an elevated obstacle is detected, an obstacle detection signal is transmitted by an AM transmitter through antenna 86 to an AM receiver 84 where it is heard by visually impaired person 80. The protective zone provided for a cane user with this arrangement is quite limited and the obstacles detected can not be identified to be a passer or a stationary object.
In U.S. Pat. No. 3,546,467, a relatively costly and complex mobility cane utilizing a plurality of aesthetically objectionable, object detecting, coherent (laser) sensor pairs, is described. Highly directional transmitting and receiving sensors are mounted in a spaced relation on the cane shank. The ability to adjust the object sensors to the desired maximum object detection range is dependent upon the ability to mechanically set the angular position of each sensor with respect to the cane shank. Accordingly, an object must actually intersect a relatively narrow light beam in order to be detected and the protective zone is also very limited.
U.S. Pat. No. 2,496,639 discloses a mobility cane employing a pair of ultrasonic energy transmitting and receiving piezoelectric transducers. This particular cane is less complex than the above-mentioned U.S. Pat. No. 3,546,467. However, it suffers all of the shortcomings of the U.S. Pat. No. 2,496,639.
According to the present invention, an electronic talking stick for the blind includes a telescopic supporting rod, a control box, a handle mounted on the supporting rod and a free steering caster mounted under the control box. The handle and the control box are provided with detecting device and processing system to automatically detect road obstructions and convert detected signals into voice to inform the user or the person detected. According to the present invention, the supporting rod is rotatable and telescopic, and the DC power supply is rechargeable.